1 / 11

IETF 69 BLISS WG meeting

IETF 69 BLISS WG meeting. Automated Handling draft-elwell-bliss-dnd-00. Overview. The Automated Handling topic in the BLISS charter is intended to cover features like DND, CFU, CFNA The present draft addresses only DND (identified as a specific topic in an earlier charter proposal)

Download Presentation

IETF 69 BLISS WG meeting

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. IETF 69 BLISS WG meeting Automated Handling draft-elwell-bliss-dnd-00

  2. Overview • The Automated Handling topic in the BLISS charter is intended to cover features like DND, CFU, CFNA • The present draft addresses only DND (identified as a specific topic in an earlier charter proposal) • Aims of this session: • Discuss direction to be taken for DND • Discuss expansion to address the wider automated handling topic

  3. DND – problems to be solved? • Indicating a DND condition to a proxy (which might take specific action, such as forward to voicemail) • Scope of such an indication (use of 6xx) • Indicating a DND condition to a caller when call is rejected because of DND • Indicating a DND condition in presence

  4. Indicating DND to a proxy • Needs to be an explicit indication if proxy is to take specific action (reason phrase not sufficient), e.g.: • 480 • 480 + retry • 603 • New 4xx • New 6xx

  5. Scope of 6xx • If use 603 or new 6xx, how should this affect forking and retargeting: • Do not fork or retarget to any other contacts for this AoR (cancel any existing branches)? • Do not fork or retarget to any other contacts for any AoR (cancel any existing branches)? • Is this something that needs fixing in general for 6xx responses (RFC 3261 not clear)?

  6. Indicating DND condition to caller • Are requirements different from indicating DND to proxy? • May wish to hide the condition from a caller: • use 486 Busy Here, perhaps with Retry-After • use 180 followed by 408 • Where condition is to be indicated, reason phrase could be used (but language problem) • Is it sufficient just to rely on proxy to conceal information from caller (e.g., by changing response code) if policy is to reject call rather than forward to voicemail etc.? • HERFP problem – prioritisation of DND response compared with responses from other branches

  7. Indicating DND condition in presence • Is there any desire to extend RPID to give an explicit indication of DND? • Would this be in conjunction with “open” rather than “closed”?

  8. DND – problems that don’t need solving? • Do we need SIP means for setting / clearing DND at a proxy? • Assumed not • Do we need SIP means for overriding DND? • Assumed RFC 4412 (resource priority) could be used without further standardisation

  9. Similarity between DND and other automated handling features (CFU/CFNR) • DND can result in forwarding • DND and forwarding can both be initiated by UAS or proxy • Initiation by proxy requires some means of making the proxy aware of the condition and action to be taken

  10. Differences between DND and other automated handling features (CFU/CFNR) • DND does not necessarily result in forwarding (can lead to simple rejection) • Forwarding as result of DND can be initiated at a different place from DND itself (UAS initiates DND / proxy initiates forwarding) • DND has problems to be solved concerning how to indicate the condition in SIP and in presence • Unclear what problems (if any) need to be solved for CFU/CFNR

  11. Proposal concerning expansion to cover automated handling in total • The differences between DND and CFU/CFNR seem to outweigh the similarities • although CFU/CFNR not yet investigated • Therefore makes sense to treat DND and forwarding as different functional primitives • DND can, of course, lead to forwarding. This is just one example of many potential interactions between functional primitives.

More Related